Picture frame



FIG. 1 is a perspective view of a picture frame showing my new design;

FIG. 2 is a front view thereof, the rear view being identical;

FIG. 3 is a left side view thereof, the right side view being identical;

FIG. 4 is a top view thereof; and,

FIG. 5 is a bottom view thereof.

The dashed lines in FIGS. 1-5 are shown for environmental purposes onlyand form no part of the claimed design.

The ornamental design for a picture frame, as shown and described.